Rock fall events and other similar events (e.g. avalanches and washouts) which take place in a vicinity of railway tracks can damage the track, can damage passing trains and, in some cases, can derail passing trains which can in turn cause significant damage to the train and to people and/or property being transported by the train. Damaged trains can cause corresponding damage to the environment. Similar events which take place in a vicinity of other transport-ways (e.g. roadways, bridges, subway tracks and the like) can cause similar damage.
Prior art technology for detecting rock fall in a vicinity of railway tracks involves so called “slide fences.” Slide fences incorporate current carrying wires which extend between fence posts alongside the railway track. Falling rock may strike and break one or more of these wires, opening the corresponding circuits and preventing current flow therethrough. This change of current flow may be detected to generate a rock fall indicator. Slide fences are unreliable, because falling rock may not strike or break a wire, but may still represent a danger to a passing train. Slide fences also tend to generate false positive results, for example, when the wire are broken by animals or the like. Additionally, if a slide fence triggers (i.e. a wire is broken), then the slide fence must be repaired (i.e. the broken wire must be replaced) and rail traffic may be delayed until the slide fence is repaired.
There is a general desire for systems and methods of rock fall detection that overcome or ameliorate these and/or other deficiencies with the prior art.